Harvey Lincoff

The Perfluorocarbon Gases in the Treatment of Retinal Detachment

Four straight chain perfluorocarbon gases that had been studied in animals were tried in 30 patients. The larger volumes injected into patients made for extended disappearance times. Two milliliters of CF4 diminished to half volume in six days and had a total disappearance time of 16 days; 0.8 ml of C2F6 diminished to half volume in 10 days and had a disappearance time of 40 days; 1 ml of C3F8 diminished to half volume in 35 days and disappeared in 70 days; 0.6 ml of C4F10 diminished to half volume in 45 days and disappeared in 120 days. The expansion potential was estimated to be the same as measured in the animal model.

Perfluorocarbon Gases in Vitreous Surgery

Fifty-six patients with complicated retinal detachments were managed with vitreous surgery and one of two perfluorocarbon gases. These gases are capable of greater expansion and greater longevity compared to sulfur hexafluoride. Forty-five patients received perfluoropropane (C3F8), eleven received perfluoroethane (C2F6). The retinas of 31 patients (55.4%) were attached at six months after the disappearance of the gas. In many instances, operations performed with air-sulfur hexafluoride mixtures had failed and the retina was subsequently reattached with the use of the perfluorocarbon gases. The major complications were increased intraocular pressure, which was usually transient, and gas-induced lens opacities.

Optical coherence tomography of pneumatic displacement of optic disc pit maculopathy

BACKGROUND The authors have previously concluded that fluid from an optic disc pit creates an inner layer separation (ILS) of the retina. An outer layer detachment (OLD) centred on the macula is a secondary phenomenon that causes a dense central scotoma. Pneumatic displacement of the OLD effects an improvement in central vision. Pathology to confirm these conclusions is lacking. Intraretinal images obtained by optical coherence tomography (OCT), however, are confirmatory. METHODS Three patients with optic disc pit maculopathy were studied with stereoscopic photographs, visual fields, and OCT before and after intravitreal gas was injected to displace the central retinal elevation to below the inferior temporal vascular arcade. RESULTS Preoperatively, OCT demonstrated an ILS that connected with the optic disc pit. External to it was an OLD that centred on the fovea and did not connect with the optic disc pit. Pneumatic displacement of the OLD was accompanied by an improvement in central vision. Long term follow up indicates that the effect of displacement may be temporary. CONCLUSION OCT confirmed the two layer structure of optic disc pit maculopathy and that the improvement in central vision after pneumatic displacement coincides with a reattachment of the OLD in the macula. It also supports the hypothesis that the ILS, which persists, provides a conduit for the continuous flow of fluid from the pit to the displaced retinal elevation.

Intraocular Injection of Lidocaine

Lidocaine was inadvertently injected intraocularly in three patients. In the one patient who had not received prior mydriatics, the drug caused immediate dilation and paralysis of the pupil and diminished visual acuity to counting fingers. Retinal function began to improve after four hours and both retinal and pupillary function recovered completely by 16 hours. A second patient also recovered completely. The third patient developed a permanent field defect. The effects of intraocular lidocaine were then studied in an animal model. Lidocaine temporarily paralyzed the pupil in mydriasis and temporarily extinguished the b-wave of the electroretinogram. Light and electron microscopy study of the retina revealed no damage beyond that at the perforation site.

Perfluoropropane Gas in the Management of Proliferative Vitreoretinopathy

Perfluoropropane (C3F8), an expanding fluorinated hydrocarbon gas, was used as an adjunct to vitreous surgery in the management of 18 patients with retinal detachment complicated by proliferative vitreoretinopathy. Ten patients had reattached retinas six months after disappearance of the gas. The average intraocular longevity of the gas in successful cases was 92 days; that in failed cases was 62.7 days. This difference was not statistically significant. However, internal retinal tamponade by longer-lasting gases appears to increase the rate of retinal reattachment in the surgical management of proliferative vitreoretinopathy.

Optic Coherence Tomography of Optic Disk Pit Maculopathy

PURPOSE To define the structure of optic disk pit maculopathy. METHODS A patient was examined with optic coherence tomography before and after an intravitreal gas tamponade. RESULTS Before intravitreal gas injection, optic coherence tomography defined a separation between the inner and outer layers of the retina that connected with the optic disk pit. An outer retinal layer detachment that centered on the fovea was also present. After pneumatic displacement of the intraretinal and subretinal fluid, optic coherence tomography disclosed that the two layers were opposed and in contact with the retinal pigment epithelium. CONCLUSIONS Optic coherence tomography confirmed the two-layer structure of optic disk pit maculopathy and demonstrated the positive effect of pneumatic displacement.

Infection After Sponge Implantation for Scleral Buckling

In one series of 900 explant scleral buckling procedures, 31 had to be removed over seven years because of contamination. Of 1,000 explants from a parallel series, 27 had to be removed. In the second series, requirement of a sterile conjunctiva preoperatively and the use of prophylactic antibiotics postoperatively did not significantly reduce the rate of infection.

A temporary balloon buckle for the treatment of small retinal detachments.

An inflatable silicone explant has been used to treat small retinal detachments. The device is inserted through the conjunctiva at the oral and expanded beneath the retinal break. Subretinal fluid absorbs because the intrusion of the balloon closes the retinal break. Adhesion is obtained by transconjunctival cryopexy or laser coagulation. The balloon, which is unsecured by sutures, is deflated and withdrawn after one week.

Results of a Temporary Balloon Buckle in the Treatment of 500 Retinal Detachments and a Comparison With Pneumatic Retinopexy

Five hundred detachments with a single break or a group of breaks close together were treated with parabulbar balloon and cryopexy in Tübingen between November 1980 and September 1986. Follow-up ranged from six to 91 months. Primary attachment was achieved in 466 eyes (93%). Twelve (2.4%) redetached after the balloon was removed. After a second operation, 490 eyes (98%) were attached and after a third, 493 (99%) were attached. The results with the extraocular balloon were compared with results of a similar group of detachments treated with an intraocular gas bubble. The primary attachment rate with the expanding gas operation was 91%; 11% of these eyes redetached. Although the final attachment rate was 99%, the complications after gas were much more frequent and of serious consequence.

Cutting the encircling band.

Purpose: To report the effect of cutting the encircling band on ocular blood flow. Methods: In an interventional case series of 27 eyes with an encircling band, the ocular pulse amplitude (OPA) was measured and pulsatile ocular blood flow (POBF) derived and compared with fellow eyes. The bands were cut in 11 eyes and the POBF measured at 1 month, 3 months, and 1 year. Changes in POBF, buckle height, and visual acuity were determined. Results: The presence of the encircling band reduced the POBF to a mean of 43% (P < 0.001) of the fellow eye. Cutting the band resulted in a mean recovery to 85.6%. No retina detached after cutting, buckle height was only slightly diminished, and the visual acuity was unaffected. Conclusion: An encircling band diminishes the POBF. Cutting the band restores significant flow.